If you see the Original Anime Intro Video for Sonic CD from Sonic Jam you will see this:
This is R2, since it is between the Palmtree Panic (R1) and Collision Chaos (R3). They're ruins. We can see that the level order of Sonic 1 is very similar to the Sonic CD one.
_________________________
Sonic 1 | Sonic CD
_________________________
Green Hill | Palmtree Panic
Marble | R2
Spring Yard | Collision Chaos
Labyrinth | Tidal Tempest
As PPz was based on GHz, CCz was based on SYz and TT was based on Lz, we see that R2 perfectly matches Marble Zone, reforcing, so, the theory that R2 was based on Mz. This is the truth as many other sonic researches have confirmed. My theory is about what happened to R2 graphics.
I don't know the reasons for why was R2 scrapped, but the consequences can be found using some logical reasoning. For me, the graphics were merged with the Tidal Tempest ones and this can be proved since there are lots of Marble Zone concepts in Tidal Tempest that we will se bellow:
Remixed Art:




Reused Concepts:
Sonic 1 Original Object
Tidal Tempst Zone (Beta) Object From Sonic 1
If you play CD Sonic 510 Beta's Tidal Tempest you will see many Pallet problems, and I have an explanation for that. If R2 was merged with TTz, the Tidal Tempest zone pallet could have been tweaked to fit better with the new (and probably unedited) graphics. Let's see the pallets
TTz Present

TTz Past

TTz Good Future

TTz Bad Future

And that's it.


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